These bulimulid snails were collected by Dr. Alan Craig on
10/20/1981 at the summit of Morro Moreno, 1148 meters above sea
level and within sight of the large coastal city of Antofagasta,
northwestern Chile. The snails "only become active in the winter,
when the mountain is shrouded in constant fog," according to Dr.
Craig. Here it has rained no more than 0.2 mm in the last 40 years.
It is common, as happened at Antofagasta, for the public, especially
children, to panic when any rain falls. Further contributing to the
inimical environment is the fact that the Morro Moreno is entirely
composed of igneous rocks, and there is no obvious source of
calcium.